The pain retailers felt at the end of 2013 isn't showing signs of relief in the new year.

Following the worst holiday season since 2008—one that was underscored by dramatically reduced prices and lower margins—the heavily promotional environment has persisted into January, according to Morgan Stanley analyst Kimberly Greenberger.

"Our data indicates not only are promotions more widespread this year, but also discounts are deeper," Greenberger said in a research note. "The 'Polar Vortex' likely hindered week one, but our mall visit indicated week two was only marginally better, despite temperatures essentially in-line with last year."

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A pedestrian enters a Banana Republic store in New York, on Monday, Jan. 6, 2014.

Of the 26 retailers that Greenberger tracks, only Urban Outfitters' Anthropologie was "unequivocally less promotional" than last January, she wrote. Abercrombie & Fitch and Gap's Banana Republic were among stores that had a higher percentage of inventory on promotion, as did Macy's, which outperformed most of the sector in the November to December period.

Best Buy reported a disappointing holiday season with U.S. comps down 0.9 percent. CNBC's Courtney Reagan reports.

What's more, management at Lululemon and Express made statements earlier this month that traffic in January has continued to be weak, with Express saying it expects to remain promotional during the month. The women's clothing retailer on Thursday offered shoppers 40 percent off every item, a deal that was prevalent in its pre-holiday rush.

In all, Greenberger said the retailers she covers were 40 percent more promotional than in the same month last year.

Although January tends to be big on discounts, as retailers make room for spring products, news of heavier-than-typical promotions does not bode well for the sector, which saw its margins crushed by widespread, deep price cuts at the end of 2013. Experts had warned that retailers needed to wean consumers off of these discounts in the new year to protect their profits.

Mainly as a result of these discounts, Thomson Reuters said Tuesday that 74 retailers so far have trimmed earnings per share estimates for the fourth quarter, compared with only 15 who had positive things to say about the quarter.

Retail Metrics' Ken Perkins on Wednesday sent out his preliminary same-store sales estimates for January, saying he predicts comparable sales for the month will increase a tepid 2.7 percent, versus last January's 5.1 percent gain.

Among those expected to report on Feb. 6, Perkins predicts Gap—which posted a relatively strong 1 percent comp in the November to December period—will post its first monthly decline since September. Perennially strong L Brands—parent of Victoria's Secret—is also expected to follow up its disappointing holiday sales with a slight 0.8 percent gain in January.